commit 000228183bf17a0f64afccdda35867553c9b75f6
author Erich Keane <erich.keane@intel.com> Thu May 23 16:05:21 2019 +0000
committer Erich Keane <erich.keane@intel.com> Thu May 23 16:05:21 2019 +0000
tree 8e8ea65aad6c020c506a8cc0423c58c64eada1c0
parent 6aebd8394a2bb9e514d0eaf8c8124b79974a2ba8

Ensure builtins use the target default Calling Convention

r355317 changed builtins/allocation functions to use the default calling
convention in order to support platforms that use non-cdecl calling
conventions by default.

However the default calling convention is overridable on Windows 32 bit
implementations with some of the /G options. The intent is to permit the
user to set the calling convention of normal functions, however it
should NOT apply to builtins and C++ allocation functions.

This patch ensures that the builtin/allocation functions always use the
Target specific Calling Convention, ignoring the user overridden version
of said default.

llvm-svn: 361507

clang/lib/AST/ASTContext.cpp

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 7174504..c3a0972 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -9627,8 +9627,8 @@
 
   bool Variadic = (TypeStr[0] == '.');
 
-  FunctionType::ExtInfo EI(
-      getDefaultCallingConvention(Variadic, /*IsCXXMethod=*/false));
+  FunctionType::ExtInfo EI(getDefaultCallingConvention(
+      Variadic, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
   if (BuiltinInfo.isNoReturn(Id)) EI = EI.withNoReturn(true);
 
 
@@ -10005,34 +10005,39 @@
 }
 
 CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
-                                                    bool IsCXXMethod) const {
+                                                    bool IsCXXMethod,
+                                                    bool IsBuiltin) const {
   // Pass through to the C++ ABI object
   if (IsCXXMethod)
     return ABI->getDefaultMethodCallConv(IsVariadic);
 
-  switch (LangOpts.getDefaultCallingConv()) {
-  case LangOptions::DCC_None:
-    break;
-  case LangOptions::DCC_CDecl:
-    return CC_C;
-  case LangOptions::DCC_FastCall:
-    if (getTargetInfo().hasFeature("sse2") && !IsVariadic)
-      return CC_X86FastCall;
-    break;
-  case LangOptions::DCC_StdCall:
-    if (!IsVariadic)
-      return CC_X86StdCall;
-    break;
-  case LangOptions::DCC_VectorCall:
-    // __vectorcall cannot be applied to variadic functions.
-    if (!IsVariadic)
-      return CC_X86VectorCall;
-    break;
-  case LangOptions::DCC_RegCall:
-    // __regcall cannot be applied to variadic functions.
-    if (!IsVariadic)
-      return CC_X86RegCall;
-    break;
+  // Builtins ignore user-specified default calling convention and remain the
+  // Target's default calling convention.
+  if (!IsBuiltin) {
+    switch (LangOpts.getDefaultCallingConv()) {
+    case LangOptions::DCC_None:
+      break;
+    case LangOptions::DCC_CDecl:
+      return CC_C;
+    case LangOptions::DCC_FastCall:
+      if (getTargetInfo().hasFeature("sse2") && !IsVariadic)
+        return CC_X86FastCall;
+      break;
+    case LangOptions::DCC_StdCall:
+      if (!IsVariadic)
+        return CC_X86StdCall;
+      break;
+    case LangOptions::DCC_VectorCall:
+      // __vectorcall cannot be applied to variadic functions.
+      if (!IsVariadic)
+        return CC_X86VectorCall;
+      break;
+    case LangOptions::DCC_RegCall:
+      // __regcall cannot be applied to variadic functions.
+      if (!IsVariadic)
+        return CC_X86RegCall;
+      break;
+    }
   }
   return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
 }

clang/lib/Sema/SemaExprCXX.cpp

diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 87dc3a9..455a71b 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -2816,7 +2816,7 @@
   }
 
   FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
-      /*IsVariadic=*/false, /*IsCXXMethod=*/false));
+      /*IsVariadic=*/false, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
 
   QualType BadAllocType;
   bool HasBadAllocExceptionSpec